Your A/C is running but the house won't cool down. Before you call, here are the usual suspects — and which ones you can fix yourself.
Few things are more frustrating than an air conditioner that's running but not cooling. The good news: some causes are simple fixes you can handle yourself. Here are the seven we see most often, from easiest to most involved.
1. A dirty air filter
Start here. A clogged filter chokes airflow and is the most common reason for weak cooling. Pull it out — if you can't see light through it, replace it. This alone solves a surprising number of 'A/C not cooling' calls.
2. Wrong thermostat setting
It sounds obvious, but make sure the thermostat is set to COOL and the fan is on AUTO rather than ON. Fan set to ON blows room-temperature air between cooling cycles, which can feel like it's not working.
3. A blocked or dirty outdoor unit
The outdoor condenser releases the heat your A/C removes. If it's caked in dirt or surrounded by grass and leaves, it can't shed heat. Gently clear at least two feet around it and rinse off loose debris.
4. A frozen evaporator coil
If you see ice on the unit or refrigerant lines, turn the system off and let it thaw. Frozen coils usually trace back to a dirty filter or low refrigerant — and running a frozen system can damage the compressor.
When to call a professional
- Low refrigerant (often means a leak that needs sealing)
- A failed capacitor or contactor
- A bad compressor or fan motor
- Electrical or breaker issues
If the easy checks don't restore cooling, the remaining causes need a licensed technician and proper tools. Seeley Lake Electric offers fast, honest A/C repair across western Montana — and we'll give you the price up front before any work begins.
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